|
High Efficiency Speaker Asylum Need speakers that can rock with just one watt? You found da place. |
|
|
|
High Efficiency Speaker Asylum Need speakers that can rock with just one watt? You found da place. |
|
In Reply to: Abaham Cohen's University Classic Basshorn - Anyone here built or heard one? posted by freddyi on October 29, 2000 at 08:37:15:
Hello Freddyi,Yes, I have some very recent experience with the University Classic
bass horn; actually with the complete three way, factory built systems.Recently I purchased a pair on ebay from a seller in Idaho. These and several others had been pulled from a dumpster after being placed there as part of an auditorium remodelling. Anyway, these were built in 1974, had unfinished birch cabinets, and contained all the original drivers and crossovers.The seller has sold all that he had; many cabinets were badly smashed, so he parted them out and sold the drivers.
They were impressive on first listen, after correcting some driver phasing problems. Very lively, dynamic bass, more extended than I would have expected. Everything present except the extreme, below 30 hz. shuddering pipe organ fundamentals. I then stripped them apart, patched, sanded, and finished the cabinets a medium walnut (in part to hide the remaining flaws).
This past Friday I hauled one cabinet with bass driver (University C15W) installed over to Dr. Bruce Edgar, as we both wanted to measure this design. Nearfield frequency response was quite good, remaining within a 5dB window (plus or minus 2.5dB) from 55hz. to 300hz.and sloping off fairly rapidly from those points. Not bad at all for a front loaded horn of this size. I believe Dr. Edgar had previously calculated the design to be an exponential 50hz. flare.
Today I hauled the completed Universitys to my brother's house, to upgrade his hi fi / video system. We began listening after they had been installed on either side of his new bigscreen TV. His room is quite a bit larger than mine, and built on a concrete slab, whereas mine is not. I was not prepared for the fabulous bass they provide in his room. After working through a few CDs, we put on his laserdisc of the film Backdraft. The speakers handled all the explosions, elevated trains passing through the living room, and other heart pounding sound effects with effortless ease. This quality of natural, lifelike, realistic low frequency reproduction seems to be available only from front loaded bass horns in my experience, and these speakers confirm my belief even more. I believe that Mr. Cohen's grand design is a real sleeper, and due for a comeback.
A few details: the construction of these cabinets was sloppy in some respects. Nothing had been done to properly seal the rear chamber. Particle board dividers on either side of the driver divided the cabinet's central triangular section into three sections, the larger center section containing the woofer. These dividers were improperly cut, allowing unsealed gaps of as large as 1/4" to the side, waste sections. I sealed the rear chamber carefully. The board allowing access to the woofer had not been gasketted, and the boards in contact with it were uneven and did not permit a tight fit. I planed these down as necessary and added a gasket.The board had been installed with an inadequate number of too - short screws. I added more, and longer, deck screws.
The Cobraflex midrange horns and drivers look like they should be installed at the airport, but they perform well. I'm going to stick with my RCA theatre drivers and multicellular horns, but these Cobraflexes are not bad. Ditto for the tweeters (forget the model number), which look and sound a lot like EV T35s.The stock crossover contains two iron core inductors, three caps, and wirewound pots for mid and high frequency level.After adjusting driver levels, the system blended together very well.
The strongest attribute of these systems is...that bass! Hope this info helps.
Steve Schell
P.S. ***SHAMELESS PLUG*** Two friends and I founded the noncommercial Lansing Heritage website. Please drop on over to read about the history of James Lansing and the companies he was associated with. Better install those new printer cartridges, as we have scans of many rare old catalogs available on the site. I'm not sure how this message board works, so I'll list the URL here and in the boxes below.
http://www.audioheritage.org
This post is made possible by the generous support of people like you and our sponsors:
Follow Ups
- Re: Abaham Cohen's University Classic Basshorn - Anyone here built or heard one? - Steve Schell 00:15:13 10/30/00 (1)
- Abaham Cohen's University Classic Basshorn - What Bracing would you suggest? Anybody want to saw a pair for me? - freddyi 03:39:30 10/30/00 (0)
Top of Page ]
[ Contact Us ]
[ Support/Wish List ]
[ Copyright © 2025, Audio Asylum, all rights reserved ]
